Amalgame are generally a copy of an existing being (With his/her memories and personnalites) but without certains emotions.

Amalgame only sense Hate, Sadness, confusion, the rest of their removed emotion are blurry to them. They are genderless, devoid of genital organ. They are also invincible.

They don't have to look like Idées Noires (Idées Noires is special on its own, because he have the power of Destruction that left in it)

Idées Noires is the first Amalgame to born, it's been used has a punishment and left alone when its mission were complete.

If you want more information about this species, ask Reidréa